To fix an InSinkErator garbage disposal, attempt to rotate the disposal with a service wrench or 1/4-inch Allen wrench by turning the wrench in the hole at the bottom of the unit. If the disposal does not rotate, it could mean that the unit is clogged. Break up the clog by pulling the wrench back and forth in the disposal's bottom hole until you are able to turn it easily clockwise and counter-clockwise.
With the power to the InSinkErator shut off, check inside the grinding chamber with a flashlight to see if any debris is caught inside. It may be necessary to bail or siphon standing water from the sink before you can inspect the grinder. In some cases, silverware or plastic items that fall into the grinder can cause it to malfunction. Use pliers to remove anything that may be blocking the grinder, and test it out. Always run the water before testing the grinder after a blockage or clog.
If the InSinkErator still does not work, check the bottom of the unit to see if the breaker has tripped. This problem can arise if the disposal has been run for long periods of time or if it is connected to an overloaded circuit. Unplug other appliances that share the disposal's circuit. Push in the red overload protector reset button on the bottom of the disposal, and try restarting the unit. In some cases, it may take a few minutes before the protector can be reset.
Disposals that are hard-wired or connected to power outlets via electrical cords may fail due to tripped circuit breakers. Check the breaker box to ensure that fuses and breakers are functional. Troubleshoot the electrical outlet before scheduling a service call.